【作者】 丛林林；

【导师】 赫崇波；

【作者基本信息】 辽宁师范大学 ， 海洋生物学， 2008， 硕士

【摘要】 通过构建大连湾(DL17)和辽东湾(ZD-LDW017)两个站点夏季海水的细菌16S rRNA文库及辽东湾和海参养殖池塘秋季海水的细菌16S rRNA文库,利用16S rRNA序列比对法,对四个站点海水细菌多样性进行了分析,为海水微生物资源调查和开发及海参的水产养殖提供有益的信息。结果表明这4个水域的细菌主要为非培养细菌(Uncultured bacterium)。每个海区分别随机选取了200个克隆进行酶切谱型分析和序列测定,共得到180个不同的DNA序列,其中大连湾51个序列,分别属于13种(属);辽东湾(夏季)53个序列,分别属于13种(属);辽东湾(秋季)37个序列,分别属于10种(属);海参池塘海水39个序列,分别属于12种(属)。这4个水域各自有不同的优势菌,在大连湾和辽东湾中没有检测到致病菌,研究结果表明大连湾和辽东湾海水细菌具有丰富的多样性;海参池塘海水中检测到3种与水产养殖相关的致病菌,分别为溶藻弧菌(Vibrio.alginolyticus)、副凝聚短状杆菌( Brachybacterium qaraconglomeratum)、巨大芽孢杆菌(Bacillus megaterium)和涅斯捷连科氏菌(Nesterenkonia菌),因此控制刺参养殖环境和减少致病菌,对预防和保证刺参养殖生产具有重要作用。自2005年-2006年,连续3次从室内不同养殖时期的刺参附着基上分离优势异养细菌,以期探索刺参附着环境优势异养细菌结构与刺参发病的相关性。每次均分离出6株优势异养细菌,通过进一步对这6种优势菌株群体、个体培养特征观察、生理性状试验和16SrRNA基因序列同源性及系统发育分析表明,菌株0506-1与溶藻弧菌(Vibrio.alginolyticus)具有较高的相似性,菌株0506-2与副凝聚短状杆菌(Brachybacterium qaraconglomeratum)具有较高的相似性,菌株0506-3和0506-4具有相近的亲缘关系,两者均与Nesterenkonia sp.具有较高的相似性,菌株0506-5与巨大芽孢杆菌(Bacillus megaterium)具有较高的相似性,菌株0506-6与涅斯捷连科氏菌(Nesterenkonia菌)的相似性为99%。经人工感染试验证明,这6株菌对刺参具有不同程度的致病性。药物敏感性试验结果表明,呋南妥因、新霉素和先锋孟多对这6种优势菌株均显示高度敏感性。更多还原

【Abstract】 Content:The diversity of bacteria in Summer sea water of Dalian Bay and Liaodong Bay and the Autumn sea water of Liaodong Bay and aquaculture pond of sea cucumber were analyzed by constructing 16S rRNA libraries of bacteria samples collected from four Survey Stations, this will provide helpful information for investigating and empoldering microbial resource and sea cucumber cultured. The results showed that there were mainly uncultured bacteria in the four Stations. In Dalian Bay there were 51 unique sequences belonging to 13 bacteria species (genera), in Liaodong Bay (summer) there were 53 unique sequences belonging to 13 bacteria species (genera), in Liaodong Bay (autumn) there were 37 unique sequences belonging to 10 bacteria species (genera) and in aquaculture pond there were 39 unique sequences belonging to 12 bacteria species (genera). Different preponderant bacteria existed in the different stations, no pathogenic bacterial species were found in Dalian Bay and Liaodong Bay stations. This indicated that the bacterial diversity exists in the two stations. We found Vibrio.alginolyticus, Brachybacterium qaraconglomeratum,Bacillus megaterium and Nesterenkonia sp. in the aquaculture pond, so we should control it and reduce baleful bacteria, this will provide helpful information for the cultured of sea cucumber.The strains were studies using a polyphasic approach, which included bacillus culture character observation, biochemical characterization and phylogenetic analyses by direct sequencing of 16S rRNA genes, et al. The associated with dominance heterotrophic bacillus composing on accrete media of different periods in cultured Apostichopus japonicus and disease revealed that the dominance strains which were isolated continuously three times from the year 2005 to 2006 were identical. And the dominance strains mainly included Vibrio.alginolyticus, Brachybacterium qaraconglomeratum, Nesterenkonia sp., Bacillus megaterium. Manual infection tests showed that bacillus could cause different degree disease. Drugs sensitivity tests showed that these dominance bacillus were sensitive to Nitrofurantoin、Neomycinum and Cefamandde.更多还原